Re: [PATCH for-8.2] target/riscv/kvm: fix shadowing in kvm_riscv_(get|put)_regs_csr

["Philippe Mathieu-Daudé" <philmd@linaro.org>]

On 23/11/23 11:13, Daniel Henrique Barboza wrote:
> KVM_RISCV_GET_CSR() and KVM_RISCV_SET_CSR() use an 'int ret' variable
> that is used to do an early 'return' if ret > 0. Both are being called
> in functions that are also declaring a 'ret' integer, initialized with
> '0', and this integer is used as return of the function.
> 
> The result is that the compiler is less than pleased and is pointing
> shadowing errors:
> 
> ../target/riscv/kvm/kvm-cpu.c: In function 'kvm_riscv_get_regs_csr':
> ../target/riscv/kvm/kvm-cpu.c:90:13: error: declaration of 'ret' shadows a previous local [-Werror=shadow=compatible-local]
>     90 |         int ret = kvm_get_one_reg(cs, RISCV_CSR_REG(env, csr), &reg); \
>        |             ^~~
> ../target/riscv/kvm/kvm-cpu.c:539:5: note: in expansion of macro 'KVM_RISCV_GET_CSR'
>    539 |     KVM_RISCV_GET_CSR(cs, env, sstatus, env->mstatus);
>        |     ^~~~~~~~~~~~~~~~~
> ../target/riscv/kvm/kvm-cpu.c:536:9: note: shadowed declaration is here
>    536 |     int ret = 0;


> The macros are doing early returns for non-zero returns and the local
> 'ret' variable for both functions is used just to do 'return 0', so
> remove them from kvm_riscv_get_regs_csr() and kvm_riscv_put_regs_csr()
> and do a straight 'return 0' in the end.
> 
> For good measure let's also rename the 'ret' variables in
> KVM_RISCV_GET_CSR() and KVM_RISCV_SET_CSR() to '_ret' to make them more
> resilient to these kind of errors.
> 
> Fixes: 937f0b4512 ("target/riscv: Implement kvm_arch_get_registers")
> Signed-off-by: Daniel Henrique Barboza <dbarboza@ventanamicro.com>
> ---
>   target/riscv/kvm/kvm-cpu.c | 19 +++++++++----------
>   1 file changed, 9 insertions(+), 10 deletions(-)

Reviewed-by: Philippe Mathieu-Daudé <philmd@linaro.org>